DEUTERIUM NMR AND MORPHOLOGY STUDY OF POLYMER-DISPERSED LIQUID-CRYSTAL BRAGG GRATINGS

The orientational order in polymer-dispersed liquid crystals on holographically written volume Bragg gratings is studied using deuterium NMR. Unique spectral patterns indicate that a homeotropic liquid-crystal director configuration at the polymer interface is retained despite the small pore size ( < 100 nm). This structure coexists with liquid crystals in trapped defect structures of dimension comparable to the pore size.